The volume of the seats of airplanes is a preoccupation that aims to respond to the increase in the number of passengers transported every year. By reducing the unit volume of the seats, it is possible to reduce the spacing between two rows of seats and to increase the number of passengers that can fit inside airplanes, or quite the contrary, to increase the space allotted to each passenger or that allotted to goods. A better filling of the plane makes it possible, at constant flow of passengers on an airline, to reduce the number of flights: the fuel saved reduces accordingly discharges of greenhouse gases.
The reduction in the volume of the seats must not reduce the safety of the passengers transported. Safety standards relating to airplane seats are drastic, particularly in terms of impact resistance.
This constraint, which is the resistance and the cushioning of the passenger in the event of impacts, has for a long time led to making airplane seats intended for passengers using a metal structure and deformable cushions. The structure, consisting of a large number of metal parts, is particularly resistant in the event of impacts. But these structures are dense and make the seats quite heavy. The deformable cushions, situated at the level of the seat portion and the backrest, enable good cushioning of the passenger. But they are also quite dense and increase the total weight of the seat.
The complexity of this type of seat raises several problems, during its manufacture, its maintenance, or for the monitoring of the different parts. The greater the number of parts composing the airplane seat, the more the logistics and the manufacturing process of said seat are complex and costly. The fixings together of these different parts are often metal (typically made of stainless steel), to satisfy safety standards, and make the seat heavier. Finally, as regards the conception of the seat, each part having to satisfy safety standards, a reduction in the number of parts limits the tests to be carried out and thus the total time required for the certification of the seat. A reduction in the number of parts thus enables a reduction in the volume and the weight of the seat.
Moreover, said seats historically integrate costly functions, in weight and value terms, which are no longer adapted to the configurations of present cabins. The tilting of the backrest, for example, can no longer be used when the space between the rows of seats is reduced.
A seat skeleton, of low weight, combined with a flexible backrest, enables these drawbacks to be overcome. The shape of the seat combines the comfort of the passenger, particularly by the backrest, and optionally the seat portion, flexible, and the mechanical strength of the skeleton, in order to respect the standards in force in the transport of passengers by air. It dissociates the structural strength, assured by a single rigid component forming the skeleton, and the seat portion and the backrest of the passenger, made of a flexible material.
Nevertheless, the constraint of cushioning the passenger in good safety conditions must always be respected. The aim of the invention is thus to provide the airplane seat according to the invention with means of cushioning the passenger located behind the seat, in the event of frontal impact of the airplane, the head of said passenger situated behind rocking against the rear of the backrest of the seat situated in front of him. In the same way, an absorption means placed at the level of the seat portion makes it possible to retain the passenger in the event of downward impact of the airplane.